Desktop personal computers are valuable pieces of equipment and are frequently easily movable from one location to another. Presently, physical security can be used to ensure that a personal computer is not moved from one location to another, but such physical security is not always practical in an office environment. When a personal computer has been moved, there is no easy way of detecting its new location.
The universal serial bus ("USB") is specified to be an industry standard extension to the personal computer architecture with a focus on computer telephony interface, consumer and productivity applications. The USB architecture is described in the "Universal Serial Bus Specification", Revision 1.1, Sep. 23, 1998 available on the Internet World Wide Web at http://www.usb.org/developers/docs.html. The USB architecture provides for ease of use of peripheral expansion, transfer rates up to 12 megabits per second, protocol flexibility for mixed modes, isochronous data transfers, and asynchronous messaging. USB is a cable bus supporting data transfer between the host personal computer and a range of simultaneously accessible peripherals. The bus allows peripherals to be attached, configured, used and detached while the host and other peripherals are in operation. One host controller can support up to 127 physical devices using a tiered topology. A hub is at the centre of each star with each wire segment creating a point-to-point connection of up to 5 meters. The 5 meter limitation may be between a host and a hub or a hub function or a hub connected to another hub or function.
Pending GB patent application 99020722.7 discloses the tracking of objects within a building using a radio device associated with each object to be tracked and an array of transmitting beacons.
Pinpoint Corporation (see www.pinpointco.com) market a solution to asset location using a proprietary radio technology. Their solution is much more expensive and does not integrate into standard systems management tools.
Solutions based on detecting the personal computer's LAN attachment point only work if the attachment point can be traced through the network hubs, which is not generally the case with Ethernet or TokenRing systems. Where it is possible, continued tracking of the location depends on the physical LAN topology remaining unchanged.
So it would be desirable to provide a mechanism for determining the location of a personal computer that did not require the use of a radio device attached to each object, which could be integrated with standard systems management tools and which did not depend on knowing the computer's LAN attachment point.